A police spokesman said it was called to Tramway Rd at 4.28pm.
St John and Fire and Emergency New Zealand (Fenz) were also called to the scene.
There were initially reports that two people were inside the caravan, but a Fenz spokeswoman said it retrieved one person from the caravan.
The incident was "not as serious" as first thought and firefighters were able to stabilise the carport before helping the woman out.
She was handed into the care of St John.
A St John spokesman said one person was treated at the scene with minor injuries but did not need to be taken to hospital.
A reporter at the scene said the woman appeared shaken but was not visibly injured.